Incandescent lamp and switch



y 1941- A. F. BAHLKE 2,243,186

INCANDESCENT LAMP AND SWITCH Filed Jan. 6, 1940 Patented May 27, 1941 UNITED STATES PATENT OFFICE amuse INCANDESCENT LAMP AND swl'rcn Alfred r. Balilke, New Providence, N. 1., assignor to Utility Electric Corp., Newark, N. J, a corporation of New Jersey Application January 6, 1940, Serial No; 312,638

4Clainis.

Many incandescent electric lamps today are manufactured with a screw-threaded base connected to a lamp bulb, with a plurality of filaments in the bulb of different wattages related and combined with each other so that they may be energized either individually or all together, or all may be deenergized, so as to secure at will illumination of varying degrees of intensity. My invention contemplates particularly a multifilament lamp of this general character wherein j the filaments can be energized in succession indij vidually and together by rotation continuously inone direction of a switch operating element that constitutes a part of the lamp.

The present invention relates to that described sci-n1 vational view of the lamp base and switch with a portion of the switch operating element removed and portions of the conducting shell terminal broken away.

Figure 5 is a detached perspective view of one of the contact elements.

Specifically describing the invention, the reference character A designates the usual glass bulb or envelope of an incandescent lamp within which ismounted a plurality of filaments B and C which'have a common terminal D and individual terminals E and F respectively. Generally, the twoQfllaments B and C are of different wattage, and inaccordance with the invention are energized either individually or together as may be desired. The lamp also includes a base G which 7 includes abody shell H formed'of electrical insu- A further object is to provide such an electric incandescent lamp and switch wherein the base shall include a shell of electrical insulating material and a pair of terminal members associated with said shell in a novel and improved manner for connecting the lamp in circuit with a source of electricity.

Another object is to provide an incandescent lamp and switch which shall include a base comprising a body shell of electrical insulating material having a screw-threaded shell of conducting material thereon to form a terminal for connecting the lamp in circuit with a source of electricity, a plurality of switch contact members mounted on said body shell, and novel and improved means for electrically connecting said terminal shell to one of said contact members.

Other objects, advantages and results will be brought out by the following description when read in conjunction with the accompanying drawing in which Figure 1 is a side elevational view of an incandescent lamp and switch embodying my invention.

Figure 2 is a horizontal sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a transverse vertical sectional view taken on the line 3-3 of Figure 2.

Figure 4 is an enlarged fragmentary side elelating material and having a pair of terminals 1 and 2 for connecting the lamp in circuit with a source of electricity. As shown, one of the terminals, in the present instance the terminal I,' constitutes a screw-threaded shell of conducting ma terial to be screwed into an electric lamp socket, while the other terminal 2 constitutes a rivet or the like disposed at one end of and coaxially with the body shell H. The common terminal D of the filaments B and C is permanently connected to one of the terminals of the base, preferably the central terminal 2. In accordance with the invention, a switch for controlling the circuits through the filaments B and C is mounted on the base G, preferably exteriorly thereof.

Three contact members 5, 6 and II are secured on the body shell and project from the outer circumference thereof. The shell has dove-tailed slots I extending transversely through the walls thereof and opening through the upper edge with the walls undercut from the exterior of the shell, and each contact member comprises a strip of metal 8 bent intermediate its ends to form a dovetailed projection 9 to snugly fit into one of the for example, soldered to thecorresponding contact strip B.

The body shell H has a circumferential flange or rib l4 adjacent the end thereof opposite the central terminal 2, and the contacts I, t and II are spaced circumferentially of said flange II in approximately a common plane that is normal to the axis of the shell terminal I or lamp base G, the free ends of the spring strips of the contact members projecting in the same direction circumferentially of the body shell.

The contact members cooperate with the switch operating member that is in the form of a sectional ring I of insulating material and is rotatably mounted on the base G coaxially therewith and in overlying relation to the contact members. Preferably the ring is formed of a plurality of approximately sector-shaped complemental sections I! that are applied to the base exteriorly thereof in a general plane normal to the axis of the base. As shown, there are two approximately semi-circular sections that are identical in construction.

In accordance with the invention, the sections are so constructed that they may be easily and quickly and permanently applied to the lamp base without the use of fastener elements such as rivets and screws. As shown, each section has a groove [6 in its outer periphery at each end to register with the corresponding groove of the other section, and each groove has an undercut shoulder ll facing oppositely to the shoulder of the corresponding end of the other section. An approximately U-shaped spring clip [8 has its inturned arms I!) in interlocking relation to the corresponding shoulders I1 at the juxtaposed ends of the sections i 5, for securely connecting the sections together. In applying the clips to the sections, one arm IQ of the clip is hooked under the shoulder I! at one end of one section, whereupon the clip is pressed inwardly to cause the other arm to snap over the shoulder 15 of the juxtaposed end of the other section.

The interior surface or the ring I has a circumferential groove 20 which is of a width and depth to freely receive the flange l5, as shown in Figures 3 and 4, so that said flange serves as a guide for rotation of the ring I and holds the latter against axial movement longitudinally of the base.

At the base of the groove 20 is a narrower groove 2! in which is seated a segmental conductor or contact element 22 that is preferably in the form of a round wire. This conductor has one end bent outwardly as at 23 and seated in a socket 24 in one of the sections ii for securing the conductor to the ring to rotate therewith. The length of the conductor 22 is such as it may electrically connect all of the contacts 5, 6 and l l in one position or electrically connect only two of the contact members in other positions. The contact strips are of resilient nature so as to constantly maintain spring frictional contact with the base of the groove 2|] or the'conductor 22, and also are preferably of a width to loosely enter the groove 20 so that the contact members are housed between the ring I and the flange I.

The operation of the switch will be evident from the foregoing. With the switch operating ring I in the position shown in Figure 2, the conductor 22 is out of engagement with the contact ll so that both of the filaments B and C are deenergized. Upon rotation of the ring I in the direction of the arrow of Figure 2, the conductor 22 will continue to engage the contact member H and successively individually engage the contact members I and 0 so that the filaments B and C energized, and then will en- 7 aaesnae gage all contact members so as to energize both of the filaments.

In order to permit the switch operating ring I to rotate in only one direction and thus insure energizatlon and deenergization of the filaments in the desired succession, the sections ll of the ring may have teeth or lugs 25 formed integrally therewith, projecting upwardly from the bottom of the grooves 20 and provided with radial faces or shoulders 26 to abut the ends of the contact members I, 6 and Ii, and inclined top surfaces 21 to permit the lugs or teeth to slide freely over the contact members upon rotation of the ring I in one direction. The lugs or teeth 25 are so circumferentially spaced that at least one thereof will engage one of the contact members I, 8 or II in each of the circuit controlling positions of the ring I as above described. It will thus be seen that the contact members in effect constitute spring pawls cooperating with ratchet teeth 25 to permit rotation of the ring I in only one direction.

Also it will be observed that the teeth 25 raise the contact members from the conductor 22 as the operating ring I is moved to make the circuit changes so that the circuit is completely opened between the circuit changes and the circuit is closed each time with a snap action as the contact members are released by the teeth.

It will be observed that the manner of attaching the contact members 5, 6 and II to the shell makes it unnecessary to provide holes for rivets and also provides for easy connection of the filament terminals to the contact members after the bulb has been inserted into the base.

The base is filled with an insulating cement composition 28 as usual in the art.

Preferably the strip i2 is soldered to the shell terminal I after the base of the lamp has been assembled. Also, to prevent rotation of the shell terminal on the body shell A, the shell terminal may have an end flange 29 which may be pressed or upset'into notches 30 in a shoulder H on the body shell.

It will be understood that the details of structure of the invention may be modified and changes by those skilled in the art without departing from the spirit or scope of the invention.

Having thus described my invention, what I claim is:

1. An incandescent lamp comprising a base having a central terminal, a bulb and a filament therein having one terminal electrically connected to said central terminal, wherein said base includes a moulded body shell of electrical insulating material having a longitudinal exterior groove, a conducting strip in said groove,ascrewthreaded conducting shell fitted on said body shell in electrical contact with said strip, and means for electrically connecting said strip to the other terminal of said filament.

2. An incandescent lamp comprising a base including a'hollow body shell of moulded electrical insulating material having a central end terminal and a side terminal to cooperative respectively with the terminals of a screw-threaded lamp socket, a bulb connected to said body shell, at least one filament in said bulb, an electrical connection between said central terminal of said body shell and one terminal of said filament, said body shell having a plurality f recesses opening through the sides and one end of the exterior thereof, and spaced circumferentially of the body shell, a plurality of contact members each comprising a strip of metal having an integral offset portion seated in and interlocking with the walls of one of said recesses for connecting the contact member to the shell, at least one of said contact members being electrically connected to the other terminal or said filament, while at least another contact member is electrically connected to said side terminal of the body shell, and a switch operating member coaxially rotatable on said body shell and including a conductor for electrically connectingand disconnecting the first-mentioned contact member to and from the second-mentioned contact member upon rotation of said switch operating mem:

ber.

3. The incandescent lamp set forth in claim 2 wherein said side terminal of the body shell comprises a screw-threaded conducting shell secured on and encircling said body shell, said body shell has a longitudinal groove, and said electrical connection between one of said contact members and said side terminal of the body shell comprises a strip of metal electrically connected to said one contact member. and seated in said groove in contact with said conducting shell.

4. An incandescent lamp comprising a base ineluding a hollow body shell of moulded electrical insulating material having a central end terminal and a side terminal to cooperate respectively with the terminals of a screw-threaded lamp socket, a bulb connected to said body shell. at least one filament in said bulb, an electrical connection between said central terminal of said body shell and one terminal of said filament, said body, shell having a plurality of slots spaced circumferentially of the body shell and extending transversely through the wallsthereof and opening through one end of the shell with their side walls undercut from the exterior of the shell, a plurality of contact members each comprising a strip of metal having an integral ofiset portion intermediate its ends seated in and interlocking with said undercut walls of one of said slots with the end portions of thestrip bearing on the exterior surface of said body shell for connecting said contact member to the shell, at least one of said contact members being electrically connected to the other terminal of said filament, while at least another contact member is electrically connected to said side terminal of the body shell, and a switch operating member coaxially rotatable on said body shell andincluding a conductor for electrically connecting and disconnecting the first-mentioned contact member to and from the second-mentioned contact member upon rotation of said switch operating member.

' ALFRED F. BAHLKE. 

